Electric cable.



Patented Nov. 6, I900.

W. M. HABIRSHAW.

ELECTRIC CABLE.

(Application flied Sept. 26, 1900.

(No Ilodel.)

%. Mw mfl/or UNITED STATES PATENT OFFICE.

WVILLIAM M. HABIRSI-IAV, OF NEW YORK, Y.

ELECTRIC casts,

SPECIFICATION forming part of Letters Patent No. 661,244, dated November 6, 1900.

Application filed September 26, 1900. Serial No. 31,148. (No model.)

To all whmn it may concern- Be it known that I,W1LLIAM M. HABIRsHAW, a citizen of the United States, residing at New York city, in the county and State of New York, have invented certain new and useful Improvements in Electric Oables,of which the following is a full, true, and accurate description, reference being had to the accompanying drawing.

The object of the invention which forms the subject of this application for Letters Patent is to produce a cable especially adapted for use in systems of electrical transmission involving the use of multiple circuits, especially those which are now commonly known as ti]IGG-WllG-tl'ftl]SDJlSSlOn circuits for alternating currents. Such a cable to be durable and effective for the special purposes intended requires properties not heretofore essential in ordinary cables for conveying single currents, whether continuous or alternating, or the currents of several independent circuits.

I have devised a form of cable which is well adapted for the purpose above specified in that it is capable of conveying currents of great strength, and it is reduced in size to the smallest possible degree Without impairing its insulating properties. In such a cable it is important that the strands shall be thoroughly insulated one from the other in order to avoid induction in case currents of different potentials are used in the several conductors of the same cable. It is essential also in a cable designed, as this one is, to carry heavy currents of electricity that the Whole cable be very thoroughly insulated to prevent the grounding of the current. For

this purpose a material of very high insulating qualities must be used.

The accompanying drawing represents a cross-section of my improved cable, A indicating a conductor, B a paper covering upon A, O a filling of jute, D a coating of vulcanizable rubber or the like, and E an outside covering of braided or woven material.

The cable consists of a plurality of conductors, each of which is preferably composed of a number of strands of comparatively fine wire, each of said conductors being surrounded by a covering of paper. The paper-covered conductors are assembled in a group, either parallel or twisted, together with a filling of jute fiber, giving the whole a cylindrical form. Over this I then apply a layer or coating of vulcanizable substance-such asindia-rubberand wrap or inclose the latter with a covering of braided cord or tape.

The paper covering of the conductors is or may be applied by any of the methods now practiced in the art of insulating conductors by paper, and as an additional protection the paper itself may be saturated with an insulating compound or coated with the same.

The jute filling may also be saturated or.

coated with a suitable insulating solution.

What I claim as my invention is 1. An insulated cable composed of a plurality of electric conductors, each inclosed in a coating of paper, laid together with a jute filling, and a coating or layer of vulcanizable rubber surrounding the jute filling, the whole being taped and braided, substantially as set forth.

2. A multiple-strand cable, consisting of one or more electric conductors, each inclosed in a paper covering, laid down in a bed of fibrous material, the Whole being surrounded by a layer of vulcanizable rubber, as set forth.

3. A multiple-strand cable composed of electric conductors inclosed in paper coatings and embedded in a filling of jute, a coating of vulcanizable rubber and an outside jacket of braided tape or twine, as set forth.

WILLIAM M. HABIRSHAWV.

Witnesses:

L. LAw'roN, FRED J. HALL. 

